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    <title>ShellCheck: SC2202 – Globs don't work as operands in `[ ]`. Use a loop.</title>
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    <h1>SC2202 – ShellCheck Wiki</h1>
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    <h2 id="globs-dont-work-as-operands-in---use-a-loop">Globs don't work as
operands in <code>[ ]</code>. Use a loop.</h2>
<h3 id="problematic-code">Problematic code:</h3>
<div class="sourceCode" id="cb1"><pre class="sourceCode sh"><code class="sourceCode bash"><span id="cb1-1"><a href="SC2202.html#cb1-1" aria-hidden="true" tabindex="-1"></a><span class="bu">[</span> current.log <span class="ot">-nt</span> backup/<span class="pp">*</span>.log <span class="bu">]</span> <span class="kw">&amp;&amp;</span> <span class="bu">echo</span> <span class="st">&quot;This is the latest file&quot;</span></span></code></pre></div>
<h3 id="correct-code">Correct code:</h3>
<div class="sourceCode" id="cb2"><pre class="sourceCode sh"><code class="sourceCode bash"><span id="cb2-1"><a href="SC2202.html#cb2-1" aria-hidden="true" tabindex="-1"></a><span class="va">newerThanAll</span><span class="op">=</span>true</span>
<span id="cb2-2"><a href="SC2202.html#cb2-2" aria-hidden="true" tabindex="-1"></a><span class="cf">for</span> log <span class="kw">in</span> backup/<span class="pp">*</span>.log</span>
<span id="cb2-3"><a href="SC2202.html#cb2-3" aria-hidden="true" tabindex="-1"></a><span class="cf">do</span></span>
<span id="cb2-4"><a href="SC2202.html#cb2-4" aria-hidden="true" tabindex="-1"></a>  <span class="bu">[</span> current.log <span class="ot">-nt</span> <span class="st">&quot;</span><span class="va">$log</span><span class="st">&quot;</span> <span class="bu">]</span> <span class="kw">||</span> <span class="va">newerThanAll</span><span class="op">=</span>false</span>
<span id="cb2-5"><a href="SC2202.html#cb2-5" aria-hidden="true" tabindex="-1"></a><span class="cf">done</span></span>
<span id="cb2-6"><a href="SC2202.html#cb2-6" aria-hidden="true" tabindex="-1"></a><span class="bu">[</span> <span class="st">&quot;</span><span class="va">$newerThanAll</span><span class="st">&quot;</span> <span class="ot">=</span> <span class="st">&quot;true&quot;</span> <span class="bu">]</span> <span class="kw">&amp;&amp;</span> <span class="bu">echo</span> <span class="st">&quot;This is the latest file&quot;</span></span></code></pre></div>
<h3 id="rationale">Rationale:</h3>
<p>Globs in <code>[ ]</code> will expand to a sequence of words, one per
matching filename. Meanwhile, operators work on single words.</p>
<p>The problematic code is equivalent to
<code>[ current.log -nt backup/file1.log backup/file2.log backup/file3.log ]</code>,
which is invalid syntax. A typical error message is
<code>bash: [: too many arguments</code> or
<code>dash: somefile: unexpected operator</code>.</p>
<p>Instead, use a <code>for</code> loop to iterate over matching
filenames, and apply your condition to each.</p>
<h3 id="exceptions">Exceptions:</h3>
<p>If you know your glob will only ever match one file, you can check
this explicitly and use the first file:</p>
<pre><code>set -- backup/*.log
[ $# -eq 1 ] || { echo &quot;There are too many matches.&quot;; exit 1; }
[ file.log -nt &quot;$1&quot; ] &amp;&amp; echo &quot;This is the latest file&quot;</code></pre>
<p>Alternatively, <a href="ignore.html">ignore</a> this warning.</p>
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